Hatch Fertility Blog | Egg Donation & Surrogacy Agency

Do Surrogates Share DNA with the Baby?

Written by Hatch Fertility | Jun 30, 2025 7:00:00 AM

When exploring surrogacy, many intended parents naturally ask: Can surrogates share DNA with the baby they carry?

It’s a thoughtful and important question, and the answer depends on the type of surrogacy being used.

At Hatch, we work exclusively with gestational surrogates, which means our surrogates do not share DNA with the babies they carry. Still, understanding why that’s the case, and what role a surrogate does play, can help clarify what to expect during the surrogacy journey.

What Does It Mean to Share DNA?

A child’s DNA comes entirely from the egg and sperm used to create the embryo. If someone contributes an egg or sperm, they are genetically related to and share DNA with the child. 

But if they carry the pregnancy without contributing either—as is the case with gestational surrogates—there is no genetic connection. The surrogate’s role is essential and nurturing, but not genetic.

Is a Surrogate Mother Related to the Baby?

In gestational surrogacy, a surrogate mother is not biologically related to the baby. The embryo is created using an egg and sperm from the intended parents or donors, and the surrogate’s role is to carry the pregnancy, not to pass on her genetic material.

This is an important distinction, as people often associate pregnancy with parenthood in a biological sense. But in gestational surrogacy, the connection is physical, not genetic.

The distinction is important from a legal and emotional standpoint as well. Because the surrogate has no genetic link to the baby, intended parents can be reassured that parental rights are clearly established from the start. It’s also important to work with legal professionals to secure those rights, since surrogacy laws can vary significantly depending on your state or country.

What’s the Difference Between Gestational and Traditional Surrogacy?

In traditional surrogacy, the surrogate uses her own egg, meaning she is both the biological and birth mother of the baby. While this approach was used more frequently in the past, it’s now extremely rare and not supported by most surrogacy professionals due to legal and emotional complexities.

Gestational surrogacy, which is the model used by Hatch,  involves no genetic link between the surrogate and the baby. The embryo is created through IVF using someone else’s egg and sperm and is then transferred to the surrogate’s uterus.

Will the Baby Look Like the Surrogate?

No,  the baby will not resemble the surrogate in a genetic sense. Because the surrogate does not contribute an egg, traits like eye color, facial structure, or height are inherited from the biological parents or donors.

While the surrogate’s health and pregnancy experience can influence how the baby grows in the womb, physical features are determined solely by the baby’s DNA, not the surrogate’s.

That said, research in epigenetics shows the womb environment can play a small but meaningful role in how genes are expressed. For example, the surrogate’s nutrition or stress levels might influence things like the baby’s birth weight or immune development. 

These influences, however, do not change the child’s DNA or cause inherited traits.

At Hatch, we prioritize the health and comfort of our surrogates by providing a comprehensive compensation and benefits package — including wellness allowances (for services like prenatal nutrition, massage, doula support, and therapy), reimbursements for lost wages, household assistance, childcare supports, and personalized gifts throughout pregnancy. 

We believe that by supporting surrogates’ well-being, we also help create the most nurturing environment for the baby.

Does a Surrogate Mother Share Blood with the Baby?

The surrogate and baby do not share blood during pregnancy.

Instead, they are connected through the placenta, which acts as a filter. It allows nutrients and oxygen to pass from the surrogate to the baby while keeping their blood supplies separate. This barrier protects both the baby and the surrogate and ensures they remain physiologically distinct.

Some studies have found that a small number of cells may pass between mother and baby during pregnancy, a phenomenon known as microchimerism. While scientifically interesting, this does not create a meaningful genetic link between the surrogate and child.

Can a Surrogate Influence the Baby in Other Ways?

Yes, but not genetically. This is where epigenetics comes in. Epigenetics refers to how environmental factors in the womb can affect how a baby’s genes are expressed (without changing the genes themselves).

Things like the surrogate’s nutrition, stress levels, and overall health may have a subtle impact on fetal development, such as influencing birth weight or immune strength. However, these influences do not alter the baby’s DNA, nor do they create a biological connection between the surrogate and the child.

Final Thoughts

If you’re working with a gestational surrogate, she won’t share DNA with your baby, and she won’t be biologically related to them. Her role is to provide a healthy, nurturing environment for the baby’s growth and development, but the child’s genetic identity comes entirely from the egg and sperm used during IVF.

Understanding the difference between gestational and traditional surrogacy can offer clarity and reassurance for intended parents. At Hatch, we’re here to support you every step of the way with guidance, transparency, and care.

Learn more about the financial side of surrogacy in our guide to surrogacy expenses or explore your options for surrogacy financing.

Frequently Asked Questions About Surrogates and DNA

Can Surrogates Pass on DNA?

Surrogates cannot pass on DNA in gestational surrogacy. The DNA comes entirely from the egg and sperm used to create the embryo.

Do Surrogates Pass Traits to the Baby?

No. Traits like appearance and genetic health risks come from the genetic parents or donors.

Does the Baby Inherit Anything From the Surrogate?

The baby may be influenced by the surrogate’s womb environment (nutrition, health), but this does not affect DNA.

Will My Baby Resemble the Surrogate?

No. The baby’s resemblance comes from the biological parents or donors, not the surrogate.

Do the Surrogate and Baby Share Blood?

No. Their blood supplies remain separate thanks to the placenta, which ensures safety for both.